1. Field of the Invention
The present invention relates to a call registration apparatus for an elevator system in which a single signal line is used for a call button and a call registration lamp in an elevator cage.
2. Description of the Prior Art
Call registration apparatuses for elevators include so-called two-line type call registration apparatuses in which individual signal lines are used for a call button and for call registration lamp and so- called one-line type call registration apparatuses in which single signal line is used for a call button as well as a call registration lamp.
FIG. 4 is a circuit diagram showing the main portions of a one-line type call registration apparatus in which one end of a call button 1 is connected to ground and a signal line 7 is led out from the other end of the call button 1. One end of each of a call registration lamp 2 and a relay 10 are connected to the signal line 7. The other end of the call registration lamp 2 is connected to a DC source and the other end of the relay 10 is connected to the DC source through a contact which is made to open when a cage arrives at a floor. The signal line 7 is connected to ground through a normally open contact 11 of the relay 10.
When a user of an elevator pushes the call button 1, in FIG. 4 the call registration lamp 2 is turned on and the relay 10 is excited. The excitation of the relay 10 makes the contact 11 close to form a self-holding circuit, so that the relay 10 is self-held even if the call button 1 is released. Thus, a call is registered and the call registration lamp 2 is kept in its lighted state. When the elevator stops at the floor in response to the call, the contact 12 is opened so that the self holding of the relay 10 is released and the call is also canceled so that the call registration lamp 2 is turned off.
In an elevator system provided in a building for use for numbers of unspecified users, it is advantageous from the standpoint of simplification and is used only for use to provide single-functional operation buttons on an car operating panel such that, for example, a call button is used only for registering a call, a door open button is used only to open a door, a door close button has only a function to close the door, and so on.
On the other hand, in a so-called home elevator system, which is an elevator system provided for home use there is no particular problem even if each button can be used to perform a plurality of functions. For example, a button provided on an car operating panel acts as a call button as well as a door close button because only specified persons use the elevator system. The provision of such a configuration reduces the cost of the elevator system in portion to the reduction in the number of operating buttons.
In a configuration in which the circuit is arranged to use the same signal for call registration and door closing by a single pushing operation of an operating button, however, a user may sometimes become confused. There is no trouble even if the door closing is performed at the same time that call registration is made by a person who gets into a cage. However, in the case where a user who has gotten into a cage has registered a call for the third floor and, the cage stops at the second floor in response to a hall call at the second floor and another user going to the third floor gets into the cage at the second floor, it is impossible to perform door closing by means of the call button because call registration has already been made.
In this regard, it is desirable to make the circuit arrangement such that call registration is performed when an operating button is pushed once and door closing is performed when the same operating button is pushed again.
In the above-mentioned conventional one-line type call registration apparatus, however, there has been the problem that if the call registration lamp 2 has been once turned on by the depression of the call button 1, the state of the signal line 7 cannot be changed even if the call button 1 is pushed again and it is therefore impossible to add a new operational function to the call button 1.